The present invention relates to sound-film motion-picture projectors of the type used for dubbing, rerecording or other editing or special-effects work. The above-identified commonly assigned copending patent application discloses a projection system of this type designed to greatly facilitate the work done when, for example, dubbing or rerecording. First, the operator establishes the scene-transition locations on the film where recording-transition effects are to be performed. Such an effect may be an audio fadeover coinciding with an image-fadeover transition, or a simple audio fade-out at the end of a scene, a simple audio fade-in at the start of a scene, or a fade-in, fade-out or fadeover to be effected right in the middle of a scene. To facilitate such work, that application discloses a system wherein the operator advances the film, either manually or during normal-speed full-light projection; when the start of a scene is being projected the operator presses a store button, and a minicomputer stores the frame count for the scene-start; likewise when the end of the scene is being projected the operator again presses the store button, and the minicomputer stores the frame count for the scene-end. After this scene-start and scene-end frame-count information has been stored and other programming of the system finished, dubbing or rerecording work starts. The operator switches the system over into automatic or semiautomatic operation, and among the things the system then does is to perform a high-speed rewind to a location ahead of the scene-start, followed by a switchover into forwards transport, and including the increasing and/or decreasing of the recording level pertaining to one or more sources of audio information at the times proper for the desired scene-transition effect, these operations being performed automatically or semiautomatically, e.g., when a certain amount of operator intervention is to be provided for. With that system, the operator may program the system and then dub on a scene-by-scene basis; i.e., first he stores the scene-start and scene-end frame counts for one scene, whereafter he dubs that scene, and only then begins work on the next scene. Alternatively, the operator may command storage of the scene-start and scene-end frame counts for all the scenes on the whole film, and only thereafter begin to dub the thusly defined scenes, one after another.
Whether working exclusively scene-by-scene or on a whole-film basis, a certain amount of confusion can arise, during the initial storing of scene-start and scene-end frame counts, during the subsequent dubbing or other recording work, and during the runthroughs for evaluating the success of the work done. When initially storing the scene-start and scene-end frame counts, after the first attempt to store the correct values, and before proceeding to dub, the operator will usually want rewind followed by forwards normal-speed projection, just to check the accuracy of the frame count storage before continuing with the dubbing of that scene or with the storing of frame-count information for the next scene. Likewise, during the dubbing per se, particularly if all operations are not performed entirely automatically, the operator needs to known when he is nearing the start of the scene of interest, when he is nearing the end of the scene of interest, when he has passed the end of the scene of interest, and so forth. The projected image will itself often constitute such information, but not necessarily, e.g., when the correlation between the audio information to be dubbed and the image information is not of a simple and self-evident character; likewise, the operator's attention will be diverted away from operations which he performs or whose automatic performance he is to monitor, if he must steadily refer to the projected image information as his source of reference-location information. If, instead of watching the projected image information per se, the operator monitors the projector's frame counter, this can be equally distracting, because the number displayed on the counter is raw information which the operator must mentally interpret, possibly even with reference to a jotted-down list of frame counts reminding him of where (at which scene, or which part of a scene) he is at a given moment in his work. All this becomes particularly distracting and inefficient when the work done includes sophisticated and artful transition effects, and where scenes must be repeatedly played back after dubbing to ascertain success and repeatedly done over until a successful result has actually been achieved.